Suppr超能文献

严重脊髓损伤后发生的骨丢失与成骨减少同时发生,并先于骨血流不足。

Bone loss after severe spinal cord injury coincides with reduced bone formation and precedes bone blood flow deficits.

机构信息

Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, Florida.

Brain Rehabilitation Research Center, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, Florida.

出版信息

J Appl Physiol (1985). 2021 Oct 1;131(4):1288-1299. doi: 10.1152/japplphysiol.00444.2021. Epub 2021 Sep 2.

Abstract

Diminished bone perfusion develops in response to disuse and has been proposed as a mechanism underlying bone loss. Bone blood flow (BF) has not been investigated within the unique context of severe contusion spinal cord injury (SCI), a condition that produces neurogenic bone loss that is precipitated by disuse and other physiological consequences of central nervous system injury. Herein, 4-mo-old male Sprague-Dawley rats received T laminectomy (SHAM) or laminectomy with severe contusion SCI ( = 20/group). Time course assessments of hindlimb bone microstructure and bone perfusion were performed in vivo at 1- and 2-wk postsurgery via microcomputed tomography (microCT) and intracardiac microsphere infusion, respectively, and bone turnover indices were determined via histomorphometry. Both groups exhibited cancellous bone loss beginning in the initial postsurgical week, with cancellous and cortical bone deficits progressing only in SCI thereafter. Trabecular bone deterioration coincided with uncoupled bone turnover after SCI, as indicated by signs of ongoing osteoclast-mediated bone resorption and a near-complete absence of osteoblasts and cancellous bone formation. Bone BF was not different between groups at 1 wk, when both groups displayed bone loss. In comparison, femur and tibia perfusion was 30%-40% lower in SCI versus SHAM at 2 wk, with the most pronounced regional BF deficits occurring at the distal femur. Significant associations existed between distal femur BF and cancellous and cortical bone loss indices. Our data provide the first direct evidence indicating that bone BF deficits develop in response to SCI and temporally coincide with suppressed bone formation and with cancellous and cortical bone deterioration. We provide the first direct evidence indicating femur and tibia blood flow (BF) deficits exist in conscious (awake) rats after severe contusion spinal cord injury (SCI), with the distal femur displaying the largest BF deficits. Reduced bone perfusion temporally coincided with unopposed bone resorption, as indicated by ongoing osteoclast-mediated bone resorption and a near absence of surface-level bone formation indices, which resulted in severe cancellous and cortical microstructural deterioration after SCI.

摘要

废用导致骨灌注减少,被认为是骨丢失的机制之一。骨血流 (BF) 在严重挫伤性脊髓损伤 (SCI) 的独特情况下尚未得到研究,这种情况会导致神经源性骨丢失,其由废用和中枢神经系统损伤的其他生理后果引发。在此,4 月龄雄性 Sprague-Dawley 大鼠接受 T 椎板切除术 (SHAM) 或椎板切除术合并严重挫伤性 SCI(每组 = 20 只)。通过 microCT 进行体内的后腿骨微结构和骨灌注的时程评估,分别在手术后 1 周和 2 周进行,通过组织形态计量学测定骨转换指数。两组均在初始手术后周开始出现松质骨丢失,此后仅在 SCI 中出现松质骨和皮质骨缺陷。在 SCI 后,破骨细胞介导的骨吸收仍在进行,成骨细胞和松质骨形成几乎完全不存在,提示骨转换脱偶联,小梁骨恶化。在 1 周时,两组均出现骨丢失,两组之间的骨 BF 没有差异。相比之下,SCI 组的股骨和胫骨灌注在 2 周时比 SHAM 组低 30%-40%,在股骨远端的 BF 缺陷最明显。股骨远端 BF 与松质骨和皮质骨丢失指数之间存在显著相关性。我们的数据提供了第一个直接证据,表明骨 BF 缺陷是对 SCI 的反应而发展的,并且与抑制的骨形成以及与松质骨和皮质骨恶化同时发生。我们提供了第一个直接证据,表明在严重挫伤性脊髓损伤 (SCI) 后,清醒 (觉醒) 大鼠的股骨和胫骨血流 (BF) 存在缺陷,其中股骨远端显示最大的 BF 缺陷。减少的骨灌注与破骨细胞介导的骨吸收同时发生,这表明持续存在的骨吸收和成骨细胞表面水平的骨形成指数几乎不存在,这导致 SCI 后严重的松质骨和皮质骨微观结构恶化。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/bad1/8560388/26085e7315dd/jappl-00444-2021r01.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验